Heat exchanger



`Tune 17, 1958 R. H. sHAw HEAT EXCHANGER Filed oct. ze, 1954 w@ i ,L m L @@@wQQy gvg i 1; ,Q @Q ,Q QQ? ,m VQQQ@ ,Q W U @@@O @QQ @MAMLWWWQOQOO M m QZ w g; f 2. f w www; M

United States Patent HEAT EXCHANGER Robert H. Shaw, East Hartford, Conn., assigner to United Aircraft Corporation, East Hartford, Conn., a corporation of Delaware Application October 26, 1954, Serial No. 464,751

9 Claims. (Cl. 257-154) This invention relates to a condenser or a surface type heat exchanger.

An object of this invention is to provide a condenser or heat exchanger which is formed having small diameter tubes arranged to present rows of polygonic openings therethrough.

Another object of this invention is to provide a. condenser or heat exchanger in which metal shells or ducts fit in the polygonic openings formed by the small diameter tubes and provide the main cross-ow passages through said tubes.

A further object of this invention is to provide a condenser or heat exchanger having smooth passageways through the small tubes provided with n and stitiening' means therein.

Another object of this invention is to provide a condenser or heat exchanger having means along the inner surface of the'smooth passageways to disturb the boundary layer therethrough and to direct some uid directly around the small tubes.

Further objects and advantages will be apparent from the following specilication and drawing:

Figure 1 is a front elevational view of a condenser or heat exchanger embodying the invention.

Figure 2 is a gure taken along the line 2 2 of Figure 1 on an enlarged scale.

Figure 3 is a perspective view of an end portion of a' shell or duct provided to form a smooth passage through the small diameter tubes.

Referring to the figures, the invention is shown embodiedin a condenser or heat exchanger 1. This heat exchanger is a cross-dow type of one-pass arrangement and comprises a main flow duct or chamber 3 and a iiuid header system 5. The gas or fluid ow duct or chamber 3 is formed rectangular in shape having sides 9 and 11, a top 13 and a bottom 15. Top 13 forms the bottom of inlet header chamber 41 of the uid header system 5 which also includes sides 42, 44 and a top 46. An inlet header 48 directs the uid into the inlet header chamber 41. Sides 9 and 11 are xed to the top 13 of the chamber 3. Bottom forms the top of outlet header chamber 50 of tluid header system 5 which also includes sides 52, 54 and a bottom 56. An outlet header 58 directs the iluid out of outlet header chamber 50. Sides 9.and 11 extend over the edges of bottom 15 and slidably engage the sides 52 and 54, respectively, of the outlet header chamber. This provides for expansion and contraction of the fluid iiow tubes 20. Sides 9 and 11 are formed as solid plates while the top 13 and bottom 15 are each formed as a plate having a like series of lines of holes therein extending from one end of the chamber 3 to the other.

As viewed in Figure 1 there are nine lines of these' holes, lettered a through Each line of holes contains the same number of holes and starts at the same distance from the front of the plate in which it is located, that is, either top 13 or bottom 15. Each hole has the diam- 2,839,275 Patented June 17, 1958 eter of the inner diameter of the uid ow tube connected thereto. The distance between the centers of these holes in each line in the top 13 and bottom 15 is arranged so that the outer diameters of adjacent uid flow tubes adjacent this point barely touch. This relationship can be seen in the three lines of tubes at the right of Figure 2. While the uid iiow tubes have been described as abutting the upper plate, they may be arranged so as toextend tthrough said upper plate.

Extending through the gas ow duct or chamber 3 between top 13 and bottom 15 are -a plurality of fluid flow tubes Ztl. These tubes are arranged in nine banks, 20a, Zlib, 20c, 20d, 20e, 20j, 20g, 20h and 201'. Each fluid dow tube abuts the bottom of top 13 in a position over its respective hole and is affixed to the top. At its other end each tube abuts the top of the bottom 1S in a position over its respective hole, the hole having the same location in the bottom i5 that the hole to which the other end of the iiuid ow is attached has in the top 13, and is aflixed to the bottom 15. While the fluid flow tubes have been described as abutting the lower plate, they may be arranged so as to extend through said lower plate.

Each fluid iiow tube 26 is formed having a serpentine shape. Each end of each uid ilow tube 20 is formed as a short straight tubular section 22. These two sections are coaxially positioned. This is shown by axis A-A in Figure l. As the uid ow tube 20 extends from the lower tubular section 22 toward the other, a

yshort straight tubular section 24 forms an angle of approximately 60 with the axis A-A of the sections 22. Next, a short straight tubular section 26 extends' from the end of section 24 located away from axis A-A, in a direction parallel to the axis A-A formed by the sections 22 and for a distance approximately equal to the length of section 24. A short straight tubular section 23 then extends from the end of section 26 not attached to Isection 24, to the axis A-A forming an angle of 60 therewith. The next tubular section, section 30, extends coaxially with sections 22 from the end of section 28 which is on the axis A-A, for a distance approximately equal to the length of section 24. It is noted that tubular sections 24, 26, 28 and 30 are all of approximately the same length. This forms the tubular sections 24, 26 and 28 into a half polygonic shape or extension. The end of section 30 not attached to sec-V tion 28, then extends into another tubular section 24.

Each tubular section 24 along a uid ow tube lies in a common plane. The sequence of tubing sections 24, 26, 28 and 3d then continues until the desired height is reached, then in the last sequence, section 28 is connected to the top tubular section 22. In Figure 1, the rst row of tubes is shown as having tive half polygonic extensions extending to the left of axis A-A before the top 13 of the heat exchanger is reached.

To form the construction shown in-Figure 1 these uid flow tubes 2i? are arranged from the front of the gas ilow duct or chamber 3 to the rear in the following manner. As mentioned above, a uid flow tube 20 extends between the first hole of each line of holes of the top 13 and its respective hole in bottom 15 with the half polygonic extensions extending to the left and all lying in a plane perpendicular to the direction of gas ow through said heat exchanger. of tubes. The next row of tubes has auid flow tube 2o extending between the second hole of each line of holes of the top 13 and its respective hole in bottom 15 with the half polygonic extensions extending to the rangement of the tubes is carried on in this sequence This forms the rst rowv f 3 to' the .rear ofthe heat; exchanger, that is one row of tubes having Vits polygonic extension extending to the left with the next row of tubes having its polygonic extension extending to the right.Y While this is clearly shown ineligure: l,- Figurelgives evidence of thexsequencei aS-itprOgreSsestothe rear'of theheat exchanger. With the Vhalf .pelygonic extensionsk all lying in; planes which.

polygonic extensionsl of thefsarne bank, and the other" polygonic openings aretforrnedfbetween the Abanksof iuid iow.y tubes.-

Each'opening 32- has fixed thereinl a metal shell or duct 34. These shells can be xedly mounted by any means desired. Thesezshells or ducts 34 are each provided with Y two. tins 36 of corrugated cross section extending between the.v edges .oftwoopposing sides. These corrugated tins provide means fortransferring-heat and strengthening the structure. The corrugations provide a greater surface area for heat transfer-and permit the expansion and contraction of the metaly shells or ducts vwithout setting up undue stresses! Fins 36 are held in spaced relation by louvers 38 and 40. Louvers 38V and d() are spaced yalong the length of the metal-,shell or duct 34 to disturb the boundary layer of the gas ow tothe duct and to direct some gas directly around the fluid ilow tube. The louvers 38'.Y (see Figure 2) provideturbulence to disturb the boundary layer while louvers 4t) both direct tluid against lthe 'uid ow tubes and disturb the boundary layer through the duct34. The tins 36 and louvers 38V and 40'are merely shown in seven of the metal shells or ducts 34" so that the 'arrangement of the uid ilow tubes may be more clearly viewed. Metal shells or ducts of irregular shapes are provided around the outer edge of the heat exchanger to conform with the shape of the openings such as at 70; 72 and 73.

It is to beunderstood 'that the invention is not limited tov the specific, embodiment herein illustrated. and described, but may be used inother ways without departure frontitsU spirit asdened by the following claims.

1. Injcombination, aiow chamber, a plurality of fluid 'ow tubes passing through said chamber, said tubes being arranged in a plurality of banks, each bank of tubes having a plurality of tubes extending in a line lengthwise of saidchamber, adjacent tubes inthe line of said iuid ow tubes being formed with' complementa] oppositely offset portions to present' a `plurality of openings extending lengthwise of said chamber each having parallel side walls, at least some of said openings having a metal shell tted therein, saidl metal shell having ns located therein extending lengthwise of-#said chamber, each iin extending Vfrom one parallelside wall of the shell to another, said tins being corrugatedwith the corrugations running lengthwise of the-shell.r

2. In combination, a ow chamber, a plurality of uid flow tubes passing throughV said chamber, said tubes being arranged in lafplurality of banks, each bank of tubes havingra plurality of tubes extending Vin a line lengthwise of said chamber, adjacenttubes in the line of said iluid flow `tubes being formed with'complemental oppositely offset portions to present a plurality of openings extending lengthwise of said chamber each having parallel sidek Walls; at least certain of said openings having a metal shell fittedrtherein.said.rnetal shell having two tins located thereinextending.- lengthwise of said chamber, each nextendingffrom'one parallel side* wall 'of the shell to another, said fins dividing said metal shell"'into three passages, eachpassagehaving a louver on a shell p ortion of` its surface. Y

3. In combination, a flow-chamber, a plurality of iluid ilow tubes passing through said chamber, said tubes being arranged in a plurality of banks, each bank of tubes having a plurality of tubes extending in a line lengthwise of said chamber, adjacenttubes in the line of said fluid flow tubes beingformedwith complemental oppositely oset portions to present a plurality of polygonic openings extending lengthwise/of 4said `chamber each having pairs of parallel sidewalls, each polygonicA opening having a metal shell tted therein, each metal shell having pairsfof parallelside walls` conforming to the-:walls of said opening and having two iins located therein extending lengthwise of said'shell, each tin extending transversely of its lshell from one of the parallel side walls to the other parallel side wall, said tins being corrugated with the corrugations-.runnhig lengthwise of thel shell, a

plurality of louvers in said parallel sidewalls extending tiowtubes. passinguhroughcsaid chamber, said tubes -b'e-` ing. arranged in aplurality of banks,` each 4,bank of tubes g having a plurality of tubes extending in a. liney lengthwiseot saidchamber.formingganpluralityof rowseach uidow tubebeing formed ,in av serpentine..manner having` a 'pluralitybhalf polygonicshapes extending to one side of its axis, each half/polygonic. shape havingay tubular` section ,at its outer.. extremity which is parallel to the axis of theV uidiow tube, each uidow tube in the.

st row of `tubes having itshalf polygonic shapes extendling. towards'. oneside oflsaid chamber, each uid tlowl tube in the second row of 'tubes having its half .polygonic yshapes extending tofthe other side of said chamber, .the

tubular section of 'auidflow tube inthe tirst rowlof a..

bank being positionedabuttingand in front of the tubular section of a idiiow tube 1n the second row of an adjacent bank, polygonic openings being formed through said tubes between two adjacent banks of'tubes and between .rows ina bank of tubes.' 5. In combination, a flow chamber, a plurality ofjuid flow tubes passing through'isaid chamber, said tubes :b'eing arranged in a, plurality of banks, each bank' of tubes having aplralit'yoftubesextending in a line lengthwise of saidicham'berforming` a plurality of rows, .each lluid ow' tube 'beingjfo'rmedi inra serpentine manner having a plurality of halfpolygonic shapes extending tov one side of its'axis, eachhalf'polygonic shape having a tubular sectionvat'its outer extremity which is parallel to the irstrow of tubes 'havingits half polygonicshapes extending` towards one side of said chamber, each uidf 'ow tube Vin the secondrow ottubes'having its half polygenie shapes'extendingito-v the other-'side of said chamber, thetubularsecti'on o'a ui'd flow tube in the rstrow' of-a' bank beingpositioned abuttingl and `in frontof the tubular section of a fluid flow tube yinthe second row ol an adjacentV bank, polygonic openings beingv formed through said tubes betweentwo adjacent banks of tubes and between rowsV in a bank of tubes, at least some of said openings having ain-letal shellpositioned therein, saidrk metal shell havingiins located therein, each lin extend# ing` from one sideiof the shelltoanother, said ns beingcorrugated with.V corrugations running lengthwise ot theshell. t

6. In combination, a flow chamber, a plurality ot fluidow tubes passingthrough said chamber, said tubes beingarranged in a plurality of banks, each-bank 'of tubes havinga plurality of tubes arranged in a line 'lengths wise off said chamber, adjacent tubes Ain each bank be-A ing formed with a plurality of complemental oppositely oiset portions spaced along the length of the tubes forming a plurality of passages extending lengthwise of said chamber, said oiset portions having parallel side walls, the adjacent parallel side walls of said iow tubes in adjacent banks overlapping each other, at least some of said passages having a tubular metal shell fitted therein extending lengthwise of said chamber and having parallel side walls corresponding to the side walls of said offset tube portions, said shells having fins located therein, each iin extending from one side wall of the shel to the other parallel side wall, said iins being corrugated with the corrugations running lengthwise of said shell.

7. In combination, a flow chamber, a plurality of uid flow tubes passing through said chamber, said tubes being arranged in a plurality of banks, each bank of tubes having a plurality of tubes arranged in a line lengthwise of said chamber, adjacent tubes in each bank being formed with a plurality of complemental oppositely oset portions spaced along the length of the tubes forming a plurality of passages extending lengthwise of said chamber, said oiset portions having parallel side walls, the adjacent parallel side walls of said ow tubes in adjacent banks overlapping each other, at least some of said passages having a tubular metal shell fitted therein extending lengthwise of said chamber and having parallel side walls corresponding to the side walls of said offset tube portions, each of said shells having two ns located therein, each tin extending from one side wall of the shell to the other parallel side wall, and means for locating said tins including louvers in said parallel side walls at spaced points along the length of said shells having tabs displaced inwardly from said side walls and projecting between said iins in planes transverse to the planes of said fins.

8. In a heat exchanger, a gas ow chamber having top and bottom walls provided with vertically aligned holes therein arranged in a plurality of lines extending lengthwise of said chamber, a rst row of tubes extending between the iirst hole of each line of holes of said top and corresponding holes in said bottom, said rst row of tubes having polygonic extensions spaced along the length of the tubes and extending to the left and all lying in a plane perpendicular to the direction of gas flow through said heat exchanger, a second row of tubes extending between the second hole of each line of holes of said top and the corresponding hole in said bottom, said second row of tubes having polygonic extensions located opposite the extensions in said iirst row of tubes but extending to the right and all lying in a plane perpendicular to the direction of gas flow through said heat exchanger, the tubes in the corresponding holes of each line of holes forming banks of tubes running lengthwise of said chamber, the left and right polygonic extensions of which are complemental and dene a plurality of polygonic gas ow passages extending from front to rear of said gas chamber, said extensions having parallel side walls and the parailel side walls of the extensions in one bank overlapping the adjacent side walls of the next bank.

9. In a heat exchanger, a gas flow chamber having top and bottom walls provided with vertically aligned holes therein arranged in a plurality of lines extending lengthwisc of said chamber, a first row of tubes extending between the irst hole of each line of holes of said top and corresponding holes in said bottom, said first row of tubes having polygonic extensions spaced along the length of the tubes and extending to the left and all lying in a plane perpendicular to the direction of gas ow through said heat exchanger, a second row of tubes extending between the second hole of each line of holes of said top and the corresponding hole in said bottom, said second row of tubes having polygonic extensions located opposite the extensions in said first row of tubes but extending to the right and all lying in a plane perpendicular to the direction of gas flow through said heat exchanger, the tubes in the corresponding holes of each line of holes forming banks of tubes running lengthwise of said chamber, the left and right polygonic extensions of which are complemental and deiine a plurality of polygonic gas ow passages extending from front to rear of said gas chamber, said extensions having parallel side walls and the parallel side walls of the extensions in one bank overlapping the adjacent side walls of the next bank, some of said passages having a tubular metal shell fitted therein extending lengthwise of said chamber and having corresponding parallel side walls, said shell having tins 1ocated therein, each n extending from one parallel side wall of the shell to the other, said fins being corrugated with the corrugations running lengthwise of the shell.

References Cited in the le of this patent UNITED STATES PATENTS 822,996 Smith June 12, 1906 1,397,625 Fedders Nov. 22, 1921 1,969,439 Wentworth et al. Aug. 7, 1934 

